Medical diagnostic X-ray workers are one occupational group that expose to the long-term low-dose externalradiation over their working lifetime, and they may under risk of different cancers. This study aims to determinethe relationship between the occupational X-ray radiation exposure and cancer risk among these workers inJiangsu, China. We conducted Nested case-control study to investigate the occupational X-ray radiation exposureand cancer risk. Data were collected through self-administered questionnaire, which includes but not limitsto demographic data, personal behaviors and family history of cancer. Retrospective dose reconstruction wasconducted to estimate the cumulative doses of the x-ray workers. Inferential statistics, t-test and 2 tests wereused to compare the differences between each group. We used the logistic regression model to calculate the oddsratio (OR) and 95% confidence interval (CI) of cancer by adjusting the age, gender. All 34 breast cancer casesand 45 esophageal cancer cases that detected in a cohort conducted among health workers between 1950~2011were included in this presented study, and 158 cancer-free controls were selected by frequency-matched (1:2).Our study found that the occupational radiation exposure was associated with a significantly increased cancerrisk compared with the control, especially in breast cancer and esophageal cancer (adjusted OR=2.90, 95% CI:1.19-7.04 for breast cancer; OR=4.19, 95% CI: 1.87-9.38 for esophageal cancer, and OR=3.43, 95% CI: 1.92-6.12for total cancer, respectively). The occupational X-ray radiation exposure was associated with increasing cancerrisk, which indicates that proper intervention and prevention strategies may be needed in order to bring downthe occupational cancer risk.